Irish slate designated an official Heritage Stone

Valentia Slate on the roof of the Rubrics at Trinity College Dublin by Crannog Roofing and Clancy Drangan. 

Valentia Slate, a natural stone derived from Valentia Island in the Republic of Ireland has been officially recognised as a heritage stone. 

Awarded the status of 'International Union of Geological Sciences Heritage Stone', it has been used internationally, including on the floors and roofs of the House of Commons in London and Trinity College, Dublin. The status is only given to stone that has a history of significant use and which is still available for conservation purposes today.

Globally, only 55 stones are recognised by this designation and it was achieved through research by the Trinity research group Stonebuilt Ireland based in Geology in the School of Natural Sciences and led by Professor Patrick Wyse Jackson and Dr Louise Caulfield, in collaboration with colleagues at Valentia Slate Company Ltd and Carrig Conservation Consultants. Connemara Marble is the only other stone in Ireland with this recognition.

The slate which can be used in construction and domestic settings is extracted underground on Valentia Island in the same facility that was opened by Peter Fitzgerald, the Knight of Kerry, in 1816. The company operates a zero-waste policy in extracting slate for a wide variety of purposes including flooring, roofing slates, worktops and headstones. 

Valentia Island, Republic of Ireland

Professor Patrick Wyse Jackson said: “Valentia Slate is a unique stone type that only occurs in Co. Kerry. Its characteristics allowed it to be split into roofing slates but also large slabs and it was utilised for a wide variety of domestic and commercial applications. Amongst the more unusual uses were for headstones, garden benches, billiard tables, water tanks, and walling for bonded warehouses. The research project Stonebuilt Ireland, funded by the Geological Survey Ireland and Office of Public Works, enabled research on this important sustainable commodity.” 

Aidan Forde, a geologist, is owner of Valentia Slate Company Ltd and commented: “This recognition is also of the expert and hard-working staff of Valentia Slate who have made the company what it is today. This award is recognition, not only of their own efforts in keeping Valentia Slate available for use in sustainable construction, but also the work of the many generations of South Kerry people who worked at the quarry.” 

Materials expert, Peter Cox who is founder and managing director of Carrig Conservation International Limited and has forty years of experience in the conservation of historic buildings across the world concluded: “Valentia Slate is one of the purest and finest products I have come across in my forty years working in this sector. The material has been used on many very important international buildings; it is vitally important that historic materials such as Valentia Slate are available for conservation and repair of these buildings. It is an added bonus that slate is now available from an Irish source to reduce carbon in our modern construction market”. 

To read the full report published in the Irish Journal of Earth Sciences on which the Heritage Stone status is based, click here.